Chimney draft regulator



Nov. 13, 1934.. w, soN 1,9805692.

CHIMNEY DRAFT REGULATOR F iled Jan. 4, 1934 Patented Nov. 13, 1934 UNITED STATES PATENT OFFICE CHIMNEY DRAFT REGULATOR George W. Mason, Chicago, Ill.

Application January 4, 1934, Serial No. 705,191

2 Claims. (Cl. 236-45) This invention pertains to the art of draft regulation, and has reference more particularly to a known type of regulator that is located in a chimney wall, usually between the bottom of the chimney and the junction of the furnace smoke pipe or flue with the chimney; its purpose or function being to automatically lessen the effect of the up draft in the chimney on the furnace when gales or high Winds are blowing, and

thus save coal and prevent the accidental burning out of the fuel charge in the furnace especially at night or during other periods when the fire cannot receive proper attention.

Various chimney draft regulators of this type have heretofore been proposed, but, so far as I am aware, few if any of them have been put in service, due, as I believe, to the facts that they are quite complicated in structure and expensive to manufacture, inadequately reliable and efii- TZO cient in operation, difficult to adjust for sensitiveness to variations in the strength of the draft, and many of them include parts located outside the chimney that are more or less in the way in a basement and liable to accidental 525 breakage or other injury.

One object of the present invention is to provide an improved automatic chimney draft regzulator of very simple and inexpensive construction that may be readily installed in a chimney wall either during the building of the chimney or subsequently. Another object is to provide a device that shall be thoroughly reliable and efficient in operation. Another object is to provide a draft regulator that shall be very responsive to variations in the strength of the draft and can easily be adjusted to render it more or less sensitive to the up draft or suction in the chimney, and still another object is to provide a device the parts of which shall, in the closed or idle position of the shutters be contained wholly within the chimney wall.

Other objects and attendant advantages of the invention will be apparent to persons familiar with devices of this character from the following detailed description, taken in connection with the accompanying drawing, wherein I have illustrated one practical and approved form in which the invention may be embodied, and. in which:-

Figure 1 is a diagrammatic representation of a chimney, a furnace, and a furnace flue, showing a practical location of the chimney draft regulator in the chimney wall.

Fig. 2 is an outer or front elevation of the regulator.

Fig. 3 is an inner or rear elevation of the same.

Fig. 4 is a Vertical section on the line 4-4 of Fig. 3 showing the device installed in a chimney wall.

chimney flue.

In the lower portion of the wall of the chimney is a rectangular opening 10, which may be a specially formed opening, or the clean-out opening commonly made in chimneys for removing accumulated soot.

Describing now my improved automatic draf regulator, 11 designates the top wall, 12 the bottom wall, and 13 the side walls of a rectangular frame that is made to fit within the opening 10. Preferably this frame is acasting, and the same is also formed on its outer end with a marginal flange 14 that overlaps the outer edges of the opening 10, as clearly shown in Fig. 4.

On the inner sides of the side walls 13 of the frame are upper and lower pairs of hinge lugs 13 that, as best shown in Fig. 5, are formed as half bearings, and, in the case of a cast frame, may conveniently be cast with the Walls 14 and 15 designate upper and lower shutters, which are duplicates of each other and preferably consist simply of flat, thin, rectangular plates.

As shown in Figs. 2 and 5, to the outer bearings 13 These lugs and pintles are set slightly inwardly from the end edges of the shutters, and the pintles are axially offset from the outer sides of the shutters, so that said end edges may throughout their entire length slidably engage with the side walls 13 of the frame. It will also be observed that the hinge pintles 1'7 are located above the middle and below the top edge of the shutter, so that the shutter tends to close by gravity. By reference to Fig. 4 it will also be observed that the upper and lower pairs of pivot bearings 15 are located in an inclined plane that is substantially parallel with the two shutters in the fully closed position of the latter.

fully closed position of the shutters, the top edge of the upper shutter 14 contacts with the front portion of the top wall 11 of the frame within the latter, the bottom edge of the lower shutter 15 contacts with the rear portion of thebottom wall 12 of the frame within the latter, and the bottom portion of the upper shutter 14 overlaps and contacts with the top portion of the lower shutter 15; and since the vertical edges of the shutter have sliding contact with the vertical side walls 13 of' the frame, when the shutters are fully closed practically no air can pass through the opening 10, at which time all of the up draft or suction in the chimney is exerted on the furnace.

Under an abnormally strong draft in the furnace flue, such as might be caused by a strong wind or gale, the shuttersi i and 15 will swin to a greater or less open position, as indicated by the dotted and dot-and-dash lines in Fig. 4. When this acticn occurs, the draft on the furnace is lessened.

In devicescf this character it has been proposed to vary the sensitiveness of the shutter or shutters to a draft tending to open them by means of counter weights variously applied. In the preferred form of my invention I also employ a form of universally adjustable or variable counter weight, which may be adjusted between a positionin which it has substantially no influence on the shutter and a position where it has amaximum gravity influence. Describing this feature, 18 designates a fiat strip or arm that is pivotally attached at its upper end tothe shutter, preferably by the simple clamping meansillustrated in Fig. 6, wherein 19 designates a screw passed through a hole in the arm 18 and ,a registering hole in the shutter, and receiving a clamp nut 20 and, preferably, an ordinary spring washer 21 between the inner end of the nut 20 and the opposed surface of the shutter. On the free end of the arm 18 is a weight preferably taking the form of a disc 22 that also lies on the upper side of the shutter, as clearly shown in Fig. 4. Q If it is desired that the regulator shall function under comparatively light suction in the chimney flue, the weight 22 and its arm 18 are shifted to the substantially horizontal position illustrated by dotted lines in Fig. 3, wherein the wei ht has practically no effect on the shutter since it ,is substantially balanced on the pivot axis Or the latter. If it is desired to reduce the sensitiveness of the shutter to a minimum, the weight is shifted to the depending position shown by full lines in Fig. 3. Any intermediatev degree of sensitiveness may be secured by shifting the arm and Weight to an intermediate position, as illustrated by a dotand-dash position shown in Eig. 3. The weight may be thus adjuste d by slightly loosening the nut 20, swinging the armand weight to the desired position, and then tightening up the nut 20 which thus holds the arm and weight in its new position. And since the arm and weight both lie in contact with the upper surface of the shutter, no strain is imposed on the pivotal connection by the gravity effect, of. the weight, which is transmitted directlyto the shutter itself.

The described manner of pivotally mounting theshutters also permits them tobe veryeasily appliedand removed.

[In applyingthe shutter it is entered bottom edge foremost through the space in the frame above the pivot lugs 13 until the pintles 1'7 register with and enter the latter, whereupon the shutter drops by its own gravity. The reverse of these operations effects the withdrawal of the shutter, for which purpose the nut 20 forms a convenient handle for lifting the shutter free from its half bearings and then drawing it out.

Where a metal frame or casing is applied to a hole in the furnace wall, it does not" have an air tight fit with the latter unless it is set in a bed of mortar or cement. To avoid the necessity of such embedding of the frame, I form on the frame the marginal flange 14, and I then apply around the edges of the flange a suitable packing 23 of cement, tar or the like, by which the joint between the margin of the flange 14 and the chimney wall is effectively sealed against the passage of air.

It is believed that the foregoing description, taken in connection with the drawing, will clearly show how the described structure effectuates the stated. purposes and objects of the inventicn. ltfanifestl n'it also acts to prevent danger of fire from overheating of the furnace'and chimney fines, and thus constitutes an automatic safety device in that respect, as well as preventing waste of fuel. Y

. I claim:

1. In an automatic chimney draft regulator,

the combination of a rectangular frame adapted to fit an opening in a chimney wall, hinge lugs formed as half-bearings on the inner surfaces cf the side walls of said frame intermediate the upper and lower ends of said side walls, a plurality of shutters each of a length such that its end edges slidably engage with said inner'surfaces of the side walls, andhinge pintles mounted on and axially spaced from the outer surfaces of said shutters and lying inwardly of the end edges of the latter, said pintles being located above the middle and below the top edge of each shutter respectively, and each shutter being insertible and removable through the space above its cooperating pintle bearings.

2. In an automatic chimnevdraft regulator,

the combination of a rectangular frame adapted to fit an opening in a chimney wan; upper and lower pairs of binge lugs formed as half-bearings disposed in an inclined plane'on the inner surfaces of the sidewalls of said frame intermediate the upperand lower ends of said-side w alls,'upper and lower shutters each of alength such that its end edges slidably engage with lsaid'inner surfaces of theside walls,'and hinge pintles mounted on and axially spaced' '-f-rom theouter surfaces of said shutters 'and lying' inwardly or the end edges of the latter, said pintles being located above the middle and below the top edge of each shutter respectively, and each shutter i being insertible and removable through the space above its cooperating pintle bearings; the height of said shutters being such thatQin their fully closedposition, the top edge of the upper shutter contacts with the front portion of the top wall .(EQRQ N- 

